We currently use R-Drive 4.7 for imaging laptops that get sent out to work sites for data collection. Once the data is handed over to the customer, the laptops are returned to the lab and are re-imaged with the most recent version, wiping out any sensitive data that was collected on the job site.

We currently maintain a database of images from all of the laptops in use from varying manufacturers (Dell, HP, IBM, etc) but all use Windows XP/Office 2000 (with individual licenses for each). My question is can we have one image that can be used for all the laptops or one for each manufacturer rather than having an image for each individual laptop.

I think you can use a separate image for each manufacturer rather than for each laptop or one image for all. Each manufacturer supplies its own driver set for their machines. The only problem I expect is Windows and office activation, as after imaging all installations will have the same serial numbers from the image. Most likely Windows will work, whereas Office won't, but I'm not sure about legality of using such Windows.
But if the only goal of such re-imaging is to wipe some sensitive data, I recommend you to look at our wiping and computer cleaning utility R-Wipe and Clean that can be programmed to do that as a single wiping and cleaning task. And if you plan to install it on many computers, I think, volume prices will apply.